   already exist."
   [opts requires]
   (let [index (js-dependency-index opts)]
-    (letfn [(cljs-deps [coll] (filter #(not (contains? index %)) coll))]
+    (letfn [(cljs-deps [coll] (remove #(contains? index %) coll))]
      (loop [requires (cljs-deps requires)
             deps {}]
        (if (seq requires)

  (println (build '[(ns hello.core)
                    (defn ^{:export greet} greet [n] (str "Hola " n))
                    (defn ^:export sum [xs] 42)]
                  {:optimizations :simple :flags #{:pretty-print}}))

  ;; build a project with optimizations
  (build "samples/hello/src" {:optimizations :advanced})

                parse-js-ns
                (assoc :file (.getPath f) :url (to-url f))))]
    (let [js-sources (filter #(.endsWith (.getName %) ".js") (file-seq (io/file path)))]
      (filter #(seq (:provides %)) (map graph-node js-sources)))))

(def load-library (memoize load-library*))

